Clinical significance of soluble form of HLA class I molecule in Japanese patients with pancreatic cancer

In recent studies a soluble form of human leukocyte antigen class I(sHLA-I) has been found in blood, urine, ascitic fluid, and various other tissues. Research has been focused on the role of sHLA-I in the induction of immunot olerance in organ transplantation. To examine the role of sHLA-I in the imm une system of patients with malignancy, we examined serum sHLA-I levels in patients with pancreatic, biliary, hepatic malignancy, and other diseases. We examined sHLA-I levels in the sera of patients with pancreatic cancer (n = 19), benign biliary disease and chronic pancreatitis (n = 20), hepatocel lular carcinoma (n = 51), gallbladder cancer (n = 6), cholangiocellular car cinoma (n = 6), and in normal controls (n = 22), using enzyme-linked immuno sorbent assay (ELISA). In patients with pancreatic cancer we also analyzed the relationship between sHLA-I and CA19-9, and the specificity and sensiti vity of sHLA-I. When patients with acute or chronic hepatitis were excluded from analysis, the mean sHLA-I level in patients with pancreatic cancer wa s significantly higher than that of normal controls (p < 0.01) and patients with benign disease (p ( 0.01), hepatocellular carcinoma (P < 0.01), gallb ladder cancer (P < 0.05), and cholangiocarcinoma (p < 0.05). We determined a serum sHLA-I cutoff level for normal controls of 2000 ng/ml; serum levels of sHLA-I were higher than the cutoff in ren patients with pancreatic canc er, and serum levels of CA19-9 were lower than 37 IU/I in 9 of 14 patients; sensitivity and specificity were 88.2% and 85.5%, respectively. Serum leve ls of sHLA-I in pancreatic cancer patients were higher than in the other di seases, although we found that pancreatic cancer cell lines did nor produce the sHLA-I. The evaluation of serum sHLA-I levels could have clinical sign ificance in pancreatic cancer. Human Immunology 62, 615-619 (2001). (C) Ame rican Society for Histocompatibility and Immunogenetics, 2001. Published by Elsevier Science Inc.